Automotive vehicles incorporate a variety of restraint systems to provide for the safety of occupants. These systems are generally included to reduce the likelihood of injury to the occupants in a crash event, Common safety systems include front airbags, side airbags, and seatbelts. The airbags are deployed within a vehicle and expand within the passenger compartment in a crash event to serve as a cushion between the occupant and interior vehicle components such as the steering wheel, the instrument panel and the windshield.
One of the more difficult challenges for manufacturers of airbags is in the design of a system that properly responds to the out-of-position (“OOP”) occupant, and particularly to the occupant positioned close to the airbag. As a result, the same amount of airbag-expanding gas is released by the inflator without accounting for the position of the vehicle occupant, this in spite of the fact that the out-of-position occupant may not require the same level of deployment energy as compared to the in-position occupant.
In response to this challenge some manufacturers have turned to the use of a tethered vent system in which a vent door is provided and is opened during initial pressurization of the airbag. The vent door is typically situated in the airbag housing and is attached to the housing by a living hinge. The vent door is open only temporarily and closes at a later stage in the airbag deployment event by a tether attached at one end to the vent door and at the other end to the primary surface of the airbag cushion. As the airbag cushion deploys vehicle-rearward, it pulls the tether and the tether pulls the vent door closed.
While this arrangement has proven largely effective, it suffers from size limitations, particularly when the airbag is positioned in the steering wheel. Specifically, there is a limited amount of package space between the driver's-side airbag and the steering wheel.
It would be desirable to have an airbag venting system that is effective in gas ventilation but which occupies less package space than used in known arrangements.